Colloquium

Upcoming Colloquium

Visualizing Novel Phases of Matter Using the Quantum Tunneling and Photoelectric Effects
Dr. Christopher Gutiérrez, UCLA

December 4, 2023
11:00am in HSCI-102

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Abstract

Gas. Liquid. Solid. These are three phases of matter that we experience in our everyday lives. However, for electrons that reside within crystal solids, geometry and quantum mechanics can conspire to produce a spectacular variety of exotic phases. In this talk, I will describe recent experiments where we use atomic defects to induce novel "density-wave" phases in graphene, a single monolayer of ordinary graphite. We detect the presence of these new phases using complementary techniques that measure either the position or momentum of graphene's electrons. Like an archaeologist re-assembling an ancient statue from its broken pieces, these tools allow us to reconstruct and visualize the symmetry and spectroscopic signature of different density-wave phases in several graphene systems. Our results suggest a surprising sensitivity of the graphene lattice to dilute disorder and opens the door to harnessing defects to tailor the properties of two-dimensional materials.

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 Biosketch

Christopher Gutiérrez graduated from UCLA with dual B.S. degrees in physics and mathematics and a minor in classics. After a gap year doing construction work with his father, he earned a M.S. degree in physics from Cal State LA before moving onto Columbia University and attaining his Ph.D. in physics. He was a postdoctoral fellow at the National Institute of Standards and Technology (NIST) and a Prize Postdoctoral Fellow at the University of British Columbia Quantum Matter Institute before going home to join the faculty at UCLA in 2020. Besides being a scientist, Christopher is an artist who enjoys making YouTube videos to teach students all over the world how to create beautiful scientific figures.